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Evaluation of the Machine Performance Check application for TrueBeam Linac

BACKGROUND: Machine Performance Check (MPC) is an application to verify geometry and beam performances of TrueBeam Linacs, through automated checks based on their kV-MV imaging systems. In this study, preliminary tests with MPC were analyzed using all photon beam energies of our TrueBeam, comparing...

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Autores principales: Clivio, Alessandro, Vanetti, Eugenio, Rose, Steven, Nicolini, Giorgia, Belosi, Maria F, Cozzi, Luca, Baltes, Christof, Fogliata, Antonella
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2015
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4464869/
https://www.ncbi.nlm.nih.gov/pubmed/25896341
http://dx.doi.org/10.1186/s13014-015-0381-0
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author Clivio, Alessandro
Vanetti, Eugenio
Rose, Steven
Nicolini, Giorgia
Belosi, Maria F
Cozzi, Luca
Baltes, Christof
Fogliata, Antonella
author_facet Clivio, Alessandro
Vanetti, Eugenio
Rose, Steven
Nicolini, Giorgia
Belosi, Maria F
Cozzi, Luca
Baltes, Christof
Fogliata, Antonella
author_sort Clivio, Alessandro
collection PubMed
description BACKGROUND: Machine Performance Check (MPC) is an application to verify geometry and beam performances of TrueBeam Linacs, through automated checks based on their kV-MV imaging systems. In this study, preliminary tests with MPC were analyzed using all photon beam energies of our TrueBeam, comparing whenever possible with external independent checks. METHODS: Data acquisition comprises a series of 39 images (12 with kV and 27 with MV detector) acquired at predefined positions without and with the IsoCal phantom in the beam, and with particular MLC pattern settings. MPC performs geometric and dosimetric checks. The geometric checks intend to test the treatment isocenter size and its coincidence with imaging devices, the positioning accuracy of the imaging systems, the collimator, the gantry, the jaws, the MLC leaves and the couch position. The dosimetric checks: refer to a reference MV image and give the beam output, uniformity and center change relative to the reference. MPC data were acquired during 10 repetitions on different consecutive days. Alternative independent checks were performed. Geometric: routine mechanical tests, Winston-Lutz test for treatment isocenter radius. Dosimetric: the 2D array StarCheck (PTW) was used just after the MPC data acquisition. RESULTS: Results were analyzed for 6, 10, 15 MV flattened, and 6, 10 MV FFF beams. Geometric checks: treatment isocenter was between 0.31 ± 0.01 mm and 0.42 ± 0.02 mm with MPC, compared to 0.27 ± 0.01 mm averaged on all energies with the Winston-Lutz test. Coincidence of kV and MV imaging isocenters was within 0.36 ± 0.0 and 0.43 ± 0.06 mm, respectively (0.4 ± 0.1 mm with external tests). Positioning accuracy of MLC was within 0.5 mm; accuracy of jaws was 0.04 ± 0.02, 0.10 ± 0.05, −1.01 ± 0.03, 0.92 ± 0.04 mm for X1, X2, Y1, Y2 jaws, respectively, with MPC. Dosimetric tests: the output stability relative to the baseline was in average 0.15 ± 0.07% for MPC to compare with 0.3 ± 0.2% with the independent measurement. CONCLUSIONS: MPC proved to be a reliable, fast and easy to use method for checking the machine performances on both geometric and dosimetric aspects. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13014-015-0381-0) contains supplementary material, which is available to authorized users.
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spelling pubmed-44648692015-06-14 Evaluation of the Machine Performance Check application for TrueBeam Linac Clivio, Alessandro Vanetti, Eugenio Rose, Steven Nicolini, Giorgia Belosi, Maria F Cozzi, Luca Baltes, Christof Fogliata, Antonella Radiat Oncol Research BACKGROUND: Machine Performance Check (MPC) is an application to verify geometry and beam performances of TrueBeam Linacs, through automated checks based on their kV-MV imaging systems. In this study, preliminary tests with MPC were analyzed using all photon beam energies of our TrueBeam, comparing whenever possible with external independent checks. METHODS: Data acquisition comprises a series of 39 images (12 with kV and 27 with MV detector) acquired at predefined positions without and with the IsoCal phantom in the beam, and with particular MLC pattern settings. MPC performs geometric and dosimetric checks. The geometric checks intend to test the treatment isocenter size and its coincidence with imaging devices, the positioning accuracy of the imaging systems, the collimator, the gantry, the jaws, the MLC leaves and the couch position. The dosimetric checks: refer to a reference MV image and give the beam output, uniformity and center change relative to the reference. MPC data were acquired during 10 repetitions on different consecutive days. Alternative independent checks were performed. Geometric: routine mechanical tests, Winston-Lutz test for treatment isocenter radius. Dosimetric: the 2D array StarCheck (PTW) was used just after the MPC data acquisition. RESULTS: Results were analyzed for 6, 10, 15 MV flattened, and 6, 10 MV FFF beams. Geometric checks: treatment isocenter was between 0.31 ± 0.01 mm and 0.42 ± 0.02 mm with MPC, compared to 0.27 ± 0.01 mm averaged on all energies with the Winston-Lutz test. Coincidence of kV and MV imaging isocenters was within 0.36 ± 0.0 and 0.43 ± 0.06 mm, respectively (0.4 ± 0.1 mm with external tests). Positioning accuracy of MLC was within 0.5 mm; accuracy of jaws was 0.04 ± 0.02, 0.10 ± 0.05, −1.01 ± 0.03, 0.92 ± 0.04 mm for X1, X2, Y1, Y2 jaws, respectively, with MPC. Dosimetric tests: the output stability relative to the baseline was in average 0.15 ± 0.07% for MPC to compare with 0.3 ± 0.2% with the independent measurement. CONCLUSIONS: MPC proved to be a reliable, fast and easy to use method for checking the machine performances on both geometric and dosimetric aspects. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13014-015-0381-0) contains supplementary material, which is available to authorized users. BioMed Central 2015-04-21 /pmc/articles/PMC4464869/ /pubmed/25896341 http://dx.doi.org/10.1186/s13014-015-0381-0 Text en © Clivio et al.; licensee BioMed Central. 2015 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research
Clivio, Alessandro
Vanetti, Eugenio
Rose, Steven
Nicolini, Giorgia
Belosi, Maria F
Cozzi, Luca
Baltes, Christof
Fogliata, Antonella
Evaluation of the Machine Performance Check application for TrueBeam Linac
title Evaluation of the Machine Performance Check application for TrueBeam Linac
title_full Evaluation of the Machine Performance Check application for TrueBeam Linac
title_fullStr Evaluation of the Machine Performance Check application for TrueBeam Linac
title_full_unstemmed Evaluation of the Machine Performance Check application for TrueBeam Linac
title_short Evaluation of the Machine Performance Check application for TrueBeam Linac
title_sort evaluation of the machine performance check application for truebeam linac
topic Research
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4464869/
https://www.ncbi.nlm.nih.gov/pubmed/25896341
http://dx.doi.org/10.1186/s13014-015-0381-0
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